Individuals vary in their tendency to interact with others; personal hygiene is a key factor in the propagation of diseases; individuals' community structure and location might be significant in spreading epidemics. The simplest assumption of individual heterogeneity is to consider that contact rates vary with only one characteristic of an individual, such as age. Age as behavioural and physiological factor is highly correlated to the risk of infection in many diseases like influenza-like diseases [1]}, [2]}, [3]}, [4]}, pertussis [5]}, tuberculosis [6]}, [7]}, varicella [8]} and COVID-19 [9]}. Understanding the impact of age on the transmission of disease is critical for determining and implementing social-distancing and interventions, especially closing schools [10]}, [11]}, [9]}.
